[PIC] PIC12F683 Pulse Counter

[OsirisB]

Hi Guys,
I have just joined this forum and am in need of some help.
>>I am building a project using the PIC12F683 to read in a 10V pulse *refer attachment for pulse
>> The program needs to read the number of pulses for a second, then multiply that by 60 to get rpm.
>>If then checks the condition of a variable (Temp).
>> If Temp=0 and rpm>300, then the pic will set a pin output to ground for a second.
>>Another condition (seperate from the previous) also monitors another pin to check if it has been set to ground, and then sets Temp=0.
>> The pic needs to reset everytime power is switched off and on.
>> Please note that pins GP1 and GP0 running condition is not HIGH or LOW, but no connection.
>> I have attached my code *please be gentle :-D

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/*
  PIC12f683
  Clock set to 4Mhz
*/
 
unsigned int temp, PulseCount,rpm;
 
 
 
void main() {
CMCON0 = 7;    // Disable comparators
         //  543210
TRISIO = 0b00100010;  // GP1 --> Recieves GND Input from tact switch, GP5 --> 10V Pulse input for counting
                      // GP0 --> Pin set to GND when conditions are met
ANSEL = 0x00; // No analog inputs
GPIO=0;
PIE1 = 0b00000001 ;  // Enable TMR1IE
 
 
 
 temp=0;
 Pulsecount=0;
 rpm=0;
do {
  TMR1H = 0x00;
  TMR1L = 0x00;
  T1CON = 0b00000111;   // Enable Timer 1
  Delay_ms(1000);
  T1CON = 0b00000110;   // Disable Timer 1
  PulseCount = TMR1H;
  rpm= Pulsecount*60; //converts revolutions per second to revolutions per minute
       IF((rpm > 300) && (temp = 0)) {
            GPIO.GP0=0; //set the GP0 output from no connection to GND
            Temp=1;} //tracks the condition of pin GP0
            IF (GPIO.GP1=0) {//Checks if GP1 recieved GND input from no connection
              Temp=0;}
              
 
 } while(1);
 }

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[jayanth.devarayanadurga]

You can't provide 10V pulse (> 5 V) to your microcontroller. The pin will be damaged. You should make your pulse 5V or less.

 

[OsirisB]

Thank you Jayanth...
I will insert a voltage divider in the circuit